Colored composition particularly suitable for dactyloscopic purposes



atented Sept. 28, 1926.

UNITED STATES PATENT OFFICE.

GHABLES LOUIS GUILLAUll IE SELIER, OF BANDOENCT, JAVA, DUTCH EAST INDIES.

COLORED COMPOSITION PARTICULARLY SUITABLE FOR DACTYLOSCOPIG PURPOSES.

No Drawing.

Application filed November 4, 1925, Serial No. 66,851, and in Dutch East Indies April My invention relates to a new colored composition particularly suitable for dacty loscopic purposes.

In order to obtain fingerprints use has been made up to now of a kind of thick ink that is spread out or rolled out over a smooth plate. Subsequently the finger of which a print has to be made, is pressed on the plate, whereafter a print of that finger is transferred for instance to paper.

This cumbersome method has various drawbacks, one of which is that before being able to make a print, the means for executing the method must be prepared,.for instance rubbing out the ink on a plate, whereto auxiliary means, such as a roller and a plate are required.

WVith the dactyloscopic' composition or paste according to the present invention the above-mentioned drawbacks. are removed, whereas moreover the advantage is obtained that it can be more easily transported than the ingredients which are used with the above said known method.

The composition or paste according to the invention is prepared in this way, that a powder is kneaded with the thick ink to a more or less stifi paste not sticking to the fingers. Furthermore I have found it in some cases very advantageous to add some greasy substance such as oil or a fat such as castor oil, cocoanut-oil, Vaseline, sheep fat and the like. A very good paste is obtained if for instance dactyloscopic ink, graphite powder and castor oil-are mixed and kneaded together. powder also blue powder or other suitable powders may be used.

The quantity of oil added to the other materials in order to obtain a paste, depends on the nature of the oil and on the nature of the other materials forming the paste, but preferably I mix one part of oil or oils or fat or fats with two parts of ink.

The composition or paste obtained in this way can be spread out'in a flat box, where after it is directly ready for use and whereby at the same time a handy packing of the material is obtained. It may also be spread Instead of graphite out for instance on a plate or on some teX- tile fabric, but the use of a flat box as above mentioned is preferable.

The making of a print is effected as fol lows:

That part of the hand of which a print is desired, is slightly pressed on the paste, which pressing can be repeated if necessary. Subsequently the part of the hand in question is placed on the paper or the like, destined for receiving the print.

Very good results can be obtained if for instance a mixture of tallow-powder and pipeclay is kneaded together with the ink in a proportion by weight of 7: 5.

It is also possible to prepare the paste in various colors, by using for instance a colored ink. V

The advantages of the composition or paste according to the invention are, that the paste is always ready for use while it is possible to obtain a clean print.

I claim 1. As a new article of manufacture a colored composition or paste for dactyloscopic purposes comprising a powder, a thick ink and a fat which materials are thoroughly kneaded together to a more or less stiff paste.

2. As a new article of manufacture a colored composition or paste for dactyloscopic purposes comprising a powder, a thick ink and a greasy substance, which materials are thoroughly kneaded together to a more or lessstiif paste. s

3.21s a new article of manufacture a colored composition or paste for'dactyloscopic purposes comprising pipeclay and a thick ink which materials are thoroughly kneaded together to a more or less stiff paste.

4. As a new article of manufacture a colored composition or paste for dactyloscopic purposes comprising a mixture of pipeciay and tallow powder and a thick ink, which materials are thoroughly kneaded together to a more or less stiff paste.

In testimony whereof I affix my signature.

CHARLES LOUIS GUILLAUME SELIER. 

